A stint in Brussels was meant to enrich my kids. It also taught them about terror.

We thought we'd left these anxieties behind when we moved here.

Tuesday morning, I was sitting in my home office in Brussels, working on my latest children’s book when a friend texted: “Holy cow. Preliminary reports indicate one or more explosive devices have gone off at Zaventem airport.”

I immediately looked out the window at my children’s Belgian school. It’s barely a hundred yards away, and every day, rain or shine, the children enjoy a full hour of recess plus a 20-minute mid-morning break. One of the luxuries of my life here is that I’m able to hear the happy sounds of children playing on the other side of my garden wall — including my 8-year-old son and 5-year-old daughter.

This time, it was a relief to hear quiet, to know that the children were still inside. Police and ambulance sirens began to shriek in the distance, but it was easier than I thought to stay calm — at least at first. The airport is a 10-minute drive from my house. Then another friend texted: “You heard about the explosion at the metro stop?” The Maalbeek metro station was just over a mile away. Now my mouth had gone dry. What was next? I threw a sweater over my pajama top, pulled on jeans and boots, and ran to my children’s school.

***

Nine months earlier, we had flown from Dulles to Zaventem to begin a new chapter of our lives. Our party included my husband, the children, my 83-year-old mother, our 16-year-old cat and me. Our unofficial slogan was “What could go wrong?” My son vomiting from one side of the Atlantic to the other while the cat yowled in despair under the seat made the list, but terrorism was nowhere on it.

While we were certainly aware of Brussels’s supporting role in a number of recent terror attacks, including on Charlie Hebdo, its status as a second-tier European capital made it seem safer than Paris or London. If anything, its danger seemed more as an Island of the Lotus Eaters, where we might end up gorging on beer and frites with functionaries of minor European nations then wake up 20 years later, having missed all the action back in the States.

But even this wasn’t such a horrible fate. After all, part of what I hoped to leave behind in America was the culture of anxiety: I was tired of helicopter parenting, of ever-earlier academic pressure, of partisan political hysteria, of gun violence. I wanted to worry a little less and enjoy life a little more, and above all, I wanted the same for my children so they’d end up more independent and less neurotic than me. Plus, what Brussels lacked in excitement, it made up for with its proximity to cooler places. As one of our friends put it, “The best thing about Brussels is the 5:45 train to Paris.”

Then in August, just as we finally had a chance to take that train, a terrorist attacked it. We were already in Paris, on our first vacation, when we heard about the gunman who had boarded the Thalys in Brussels and attempted to shoot up the passengers before American service personnel tackled him. We decided not to tell the kids — at least until we safely made the same trip back home two days later. But it wasn’t easy to hide our jitters or downplay the presence of the heavily armed police patrolling the train.

Three months later, terrorists attacked Paris itself. We watched images of the carnage in horror, sent worried messages to our friends there, but we still felt out of harm’s way. Then it emerged that the attacks had been planned in Brussels. So a week after Paris, we woke up to discover that our town was under lockdown. Authorities cautioned us to stay inside as they conducted raids and — in a purely Belgian touch — urged us to tweet cat pictures instead of the details of police activity. Our original “What could go wrong?” slogan seemed far less amusing as the raids spread across Brussels and into our own neighborhood. Our supposedly dull adopted city had turned into Europe’s most dangerous terrorist hub.

As the authorities combed Brussels for Salah Abdeslam, the fugitive Paris bomber, I found myself back in a version of New York, where I had lived during the 9/11 attacks. For four days that fall, we stayed inside, monitored terror alert levels and made nervous forays to the closest open store, gawking at the armed soldiers in military vehicles. But unlike back in New York, I now had children, and the city’s schools were mentioned as a possible target. Naturally, I did not share this disturbing information with the kids, but with schools closed, I had to tell them something. I finally explained that the police were looking for “a bad man” and repeated a lesson I had given them in post-Sandy Hook America and had hoped never to have to give in Europe: what to do in an active-shooter situation.

When school finally reopened four days later, a police officer was stationed outside the door and parents were no longer allowed to enter the building. This gave me some sense of security, but I still gathered after drop-off with a group of mostly American mothers to try to calm our nerves. We ended up discussing the best way to stage our own raid if our kids’ schools were attacked. Not exactly the kind of carefree European morning at the cafe I had once imagined.

In the weeks that followed, there was a war-zone edginess to our lives: a quicker reflex when we heard a loud noise; an occasional moment of gut unease, such as when I took the children into a crowded Christmas market tent only to discover that it had only one entrance and a distant exit. At the last minute, the authorities canceled the traditional New Year’s fireworks festivities. We hadn’t planned to go, but it was another reminder that the authorities considered the city a crime scene waiting to happen.

As the weeks passed, however, this became our new normal. The children became used to seeing armored vehicles outside our local park. We avoided large public gatherings but eventually went back to our favorite farmer’s market, the kids unfazed by the soldiers patrolling it with machine guns. Eventually, I started taking the metro again.

When friends from Washington decided to meet us in Holland for spring break, citing concerns over security in Belgium, we thought they were being overly cautious.

When, stuck in a cab in traffic, I saw a police helicopter overhead, the driver and I calmly decided it was probably just another anti-terror raid. Ho-hum. A few days later, when Abdeslam, the suspect in the Paris attacks, was apprehended after his fingerprints were discovered in the raid, it seemed that the worst was over.

Then the terrorists struck.

***

Part of the dream of every ex-pat is that, in leaving your country behind, you can also leave behind a part of yourself. And I do worry less about certain things here: my children’s education, the quality of the food, our health care and financial security. The children have become more confident and independent. (My 5-year-old recently went on a two-night class trip to the seaside, a positive experience that she’d never have back in the United States.) But as the world grows smaller, as our actions and problems become more intertwined, it seems impossible to leave anxiety and terror behind.

By the time I arrived at my children’s school on Tuesday, a small group of parents was waiting by the door. The director of the school unlocked it to talk to us. Her son had flown out of Zaventem a few hours before the bombing, and she looked shaken. She told us that, if we liked, we could take our children home. I found my daughter in the nursery school building, then my son in gym class. He was in the middle of learning a dance the kids were going to perform at the end of the year.

“What’s happening?” they asked. “Why are we going home?”

As I held their hands tight and walked them quickly home, sirens screaming in the distance, I told them that there had been attacks in Brussels.

“Like Paris?” my son said.

“Yes.”

“Are we under lockdown again?”

“Yes.”

He took this in. He didn’t seem particularly frightened. The fact that he didn’t, that this was his world now, saddened me almost as much as everything else.